docs: def _write_related_m2m_relations(self, obj, many_to_many_relationships):
          """
          For the given `many_to_many_relationships` dict mapping field names to
          a list of object instances, apply the instance listing to the `obj`s
          named many-to-many relationship field.
          """
          for fieldname, related_objs in many_to_many_relationships.items():
              # TODO On PATCH avoid clearing existing relationships not provided?
              setattr(obj, fieldname, related_objs)